﻿int[] a = new int[7];

a[0] = 1;
a[1] = 2;

//2
Console.WriteLine(a[1]);
//0
Console.WriteLine(a[2]);

List<int> b = new List<int>();
b.Add(1);
b.Add(2);
b.Add(10);
b.Add(20);
//3 b[3]
b.Insert(0, 100);
foreach (var v in b)
{
    Console.WriteLine(v);
}
b[0] = 999;

//字典 key,value
Dictionary<string, int> c = new Dictionary<string, int>();
c.Add("1", 1);
c.Add("2", 2);
if (c.ContainsKey("1"))
{
    c["1"] = 100;
}
foreach (var v in c)
{
    Console.WriteLine(string.Format("test {0}-{1} test", v.Key, v.Value));
}

